Sparking plug for internal-combustion engines.



B. BLATTMANN. SPARKING PLUG FOR INTERNAL COMBUSTION ENGINES.

APPLICATION FILED JAN.17, 1913.

Patented Aug. 4, 1914,

Iii)

STATES PATENT ERNST BLATTMANN, 0F NONNENDAMM, NEAR BERLIN, GERMANY, ASSIGNOB. TO SIEMENS & HALSKE A. G., OF BERLIN, GERMANY, A CORPORATION OF GERMANY.

SPARRING PLUG FOR INTERNAL-COMBUSTION ENGINES.

Specification of Letters Patent Patented Aug. 4,1914.

Application filed January 17, 1913. SertalNo. 742,598.

To all whom it I'llh'j/ concern lle it known that I, linxsr Bm'rranmx, a citizen of the German Empire, and residing at Nonnendamm. near Berlin, Germany, have invented certain new and useful Imprort-ments in Sparking Plugs for Internal- (.omhustion Engines, of which the following is a. specification.

My invention relates to that type of sparking plug "for internal combustion engines in which electric sparks pass between an outer casing and an electrode within it and so ignite the gaseous mixture. Such sparking plugs are exposed toconstderahle won and tear when in operationowmg to high temperature, splashes of 011 and so forth. hence they wear out'very quickly and owing to such wear and tear often suddenly fail. causing serious irregularities in the working of the internal combustion engine.

Experience has shown that when an electrode carrier composed of steel is put into use its exposed surface gradually undergoes a change, the important result of which is a gradual increasing of the diameter of the ele trode carrier. The casing of the spark plug is not ati'ected by this action. In the class of spark plugs to which my invention relates, the electrodes are set at an angle to the ele trode carrier, the result being that the ele trodes are. forced outwardly hy the swelling action referred to. llrentually an electrode touches the casing and a short circuit is caused which prevents ignition.

'l'ho sparking plug is then shortcircuittal' and ignition no longer occurs. It is only the entral steel pin, as far as it is uncovered, which is exposed to such destructire action. The casing, which is likewise of steel and from which the sparks directly pass. remains undamaged.

A primary object. of my invention is to prolong the life of the sparking plug. and to this end l cover or coat the head of the central pin carrying the nickel electrode with a nickel cap. Moreover I secure said cap in its place by means of the nickel pin w rich passes through the carrier. In this manner firstly there is obviated a premature destruction of the electrode carriers at their ends inside the engine c linder and secondly the nickel cap is firmly old by a part of the sparking plug already existing, 2'. e. by the nickel pin, special fastening means, as rivets, being thus rendered unnecessary.

One illustrative embodiment of my invention is represented by way of example in the accompanying drawing, which gives a sectional view of the improved sparking plug.

In this drawing. S is the central steel pin having the head 7: which serves as carrier for the pin-like electrode 8.

to is the outer electrode and z the insulator.

-n is the nickel cap which completely covers the head of the electrode carrier and is sccured in place by means of the nickel pin 8.

I claim:-

In a sparking plug for internal combustion engines. the combination of a plug casing. an insulator longitudinally mounted therein. an electrode carrier axially mounted in said insulator and comprising a head portion having a tl'illlHVUl'Se bore and projecting from the insulator at the ignition end of the plug and a shank attached to said head portion, a nickel cap completely covering said projecting ,heat portion and having holes registering with said bore, and a nickel pin fitting tightly in said holes and bore and set at its ends at the predetermined sparking distance from said casing.

In testimony whereof, I have signed my name to this specification in the presence of two witnesses.

ERNST BLATTMANN.

Witnesses:

Wotan-1min Ilaurr, llnsav Ilasrnn.

Copies 0! this patent may be obtained to: an cent: each, by addressing the "Commissioner of Eaten, Washington, D. 0. 

